Levelers, such as hot levelers, are commonly used in metal sheet and plate mills, namely hot rolling mills for producing metal sheets or plates. FIG. 1 illustrates a typical leveler 100 from the operator side. As shown in FIG. 1, the leveler usually includes moveable upper work rolls 60 and stationary lower work rolls 62. The metal sheet or plate enters the leveler from entry side 64 of the leveler, passes between the upper and lower working rolls, and then leaves the leveler through exit side 66. The rolling and cooling processes of the leveler reduce remaining flatness errors and residual stresses of the metal sheets or plates passing therethrough. However, as a result of passing metal sheets or plates through the rollers, under substantial compressive forces on the metal sheets or plates, particles tend to collect on the work rolls working the metal sheets or plates, which could cause gouges, pits, and scratches of the sheet and degradation in the quality of subsequently leveled plates. Thus, the polishing and cleaning of the work rolls is crucial for the effectiveness and quality of the metal sheets or plates passing through the levelers.
Conventionally, a leveler is polished by bracing the leveler in an open position, in which top portion 42 of the leveler is raised (e.g., with a roll nest support car). An operator would physically crawl into the open leveler and use a hand grinder power tool to grind-polish the work rolls. This process is potentially dangerous and inefficient, as operators could possibly be injured while polishing the work rolls. Likewise, the extent to which the work rolls are consistently and qualitatively cleaned varies from operator to operator, or upon the mechanical condition of the grinding equipment, as well as whether or not a region on the work rolls is completely accessible to the operator attempting to polish the work rolls. Uniformity in the polishing operation can vary not only relative to the accessibility of the work roll region, it can vary as a function of the amount of time and pressure invested by the operator. The lack of uniformity can affect the resulting condition of the work rolls, and, in turn, the quality of the leveled metal sheet or plate.
More automated approaches have been utilized. One such technique, disclosed in Chinese Pat. No. CN205183384 calls for the use of a concave-shaped steel-bristle brush for cleaning a work roll.
Alternatively, Japanese Pat. No. JP200605193 discloses the use of a cleaning member that includes an inflatable air bladder that reciprocates along the length of a work roll, while the work rolls are rotated, to clean them.
The present invention has as its objectives, the goal of efficiently, effectively and safely cleaning the work rolls to ensure the quality of the metal sheets or plates being processed by the leveler itself.
These and other objectives and advantages will become apparent in view of the following disclosure, including the drawings and claims.